Lymhocyte stimulatory effect of an ether-extracted preparation of Brucella abortus.

The effect of a Brucella abortus preparation (Bru Pel) on the T- and B-lymphocyte populations is described. Bru Pel treatment of tumor-bearing mice resulted in a slight reduction in tumor size, marked splenomegaly, and statistically significant reductions in the percentages of splenic T and B lymphocytes relative to untreated tumor controls. Bru Pel was also found to cause increases in the incorporation of 3H-thymidine of phytohemagglutinin-sensitive splenic T lymphocytes and lipopolysaccharide-sensitive splenic B lymphocytes over 3H-thymidine-incorporated values for untreated tumor controls.